package com.yanwq;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.LengthFieldBasedFrameDecoder;
import io.netty.handler.codec.LengthFieldPrepender;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
import io.netty.util.CharsetUtil;

import org.apache.log4j.Logger;

public class TcpServer {
    private static final Logger logger = Logger.getLogger(TcpServer.class);
    private static final String IP = "127.0.0.1";
    private static final int PORT = 9999;
    protected static final int GROUP_SIZE = Runtime.getRuntime().availableProcessors();
    protected static final int THREAD_SIZE = 4;
    private static final EventLoopGroup bossGroup = new NioEventLoopGroup(GROUP_SIZE);
    private static final EventLoopGroup workerGroup = new NioEventLoopGroup(THREAD_SIZE);

    protected static void run() throws Exception {
        ServerBootstrap sb = new ServerBootstrap();
        sb.group(bossGroup, workerGroup);
        sb.channel(NioServerSocketChannel.class);
        sb.childHandler(new ChannelInitializer<SocketChannel>() {
            @Override
            public void initChannel(SocketChannel ch) throws Exception {
                ChannelPipeline pipeline = ch.pipeline();
                pipeline.addLast("frameDecoder", new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 4, 0, 4));
                pipeline.addLast("frameEncoder", new LengthFieldPrepender(4));
                pipeline.addLast("decoder", new StringDecoder(CharsetUtil.UTF_8));
                pipeline.addLast("encoder", new StringEncoder(CharsetUtil.UTF_8));
                pipeline.addLast(new TcpServerHandler());
            }
        });

        sb.bind(IP, PORT).sync();

        logger.info("TCP服务器已启动");
    }

    protected static void shutdown() {
        workerGroup.shutdownGracefully();
        bossGroup.shutdownGracefully();
    }

    public static void main(String[] args) throws Exception {
        logger.info("开始启动TCP服务器...");
        TcpServer.run();
    }
}

